Nitrate levels in Canterbury: limits aim to reverse the trend

There’s a significant effort in Canterbury to manage and reduce nitrate levels in groundwater caused by intensive farming over the past 20 years and more. 

In 2012 strict nitrate pollution limits were imposed on Canterbury farmers (in the Land and Water Regional Plan).

Since then even more stringent limits have been introduced in the most affected areas to begin reducing high nitrate levels (in particular Selwyn district, Ashburton Hinds, and South Coastal Canterbury).

In some areas, however, nitrate levels may continue to rise for a time because of the pollution that is already flowing through the groundwater system. 

Under the rules in the Canterbury Land and Water Regional Plan, many farmers now require a consent to farm and a Farm Environment Plan (FEP) to deal with environmental risks.

To ensure farmers are doing what they need to do, there are regular independent FEP audits which result in a grade (A, B, C, or D). Those farmers performing poorly (C or D grade) receive regular follow-up visits from Council compliance officers until their performance improves. Those performing well (A or B) are encouraged to continue to improve their environmental performance and are rewarded with fewer compliance visits and costs. 

This regime is designed to get farmers working within the environmental limits needed to protect our waterways.

The introduction of Farm Environment Plans allows us to promote agreed good management practices (GMPs) and address, in one place, the environmental rules associated with farming. 

There are defined good management practices around water use efficiency, nutrient management, effluent management, soil management, as well as farm hotspots (waste pits, offal or silage pits).

FEPs also cover riverside and drain management (erosion and sediment) as well as keeping stock out of waterways, to protect water quality. 

Figure 1. The number of farms in Canterbury that require FEPs, and their status.